I have a server with two IP addresses on its NIC: ...100 and ...200

I have the DNS server pointing at ...200

When I ping website.com, I get the IP address ...200

In IIS7, I have the website binded to http for 'All Unassigned'.

When I look at the logs, all requests show only the IP of ...100

How can this be? (website was already set up by someone else)

The problem comes into play when instead of binding to 'All Unassigned', I bind website.com to ...200

As soon as I bind it to ...200, it no longer works (because somehow it is tied to ...100)